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<a name="asio.overview.cpp2011.chrono"></a><a class="link" href="chrono.html" title="Chrono">Chrono</a>
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<p>
          Asio provides timers based on the <code class="computeroutput">std::chrono</code> facilities via
          the <a class="link" href="../../reference/basic_waitable_timer.html" title="basic_waitable_timer">basic_waitable_timer</a>
          class template. The typedefs <a class="link" href="../../reference/system_timer.html" title="system_timer">system_timer</a>,
          <a class="link" href="../../reference/steady_timer.html" title="steady_timer">steady_timer</a> and <a class="link" href="../../reference/high_resolution_timer.html" title="high_resolution_timer">high_resolution_timer</a>
          utilise the standard clocks <code class="computeroutput">system_clock</code>, <code class="computeroutput">steady_clock</code>
          and <code class="computeroutput">high_resolution_clock</code> respectively.
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<p>
          Support for the <code class="computeroutput">std::chrono</code> facilities is automatically enabled
          for <code class="literal">g++</code> 4.6 and later, when the <code class="literal">-std=c++0x</code>
          or <code class="literal">-std=gnu++0x</code> compiler options are used. (Note that,
          for <code class="literal">g++</code>, the draft-standard <code class="computeroutput">monotonic_clock</code>
          is used in place of <code class="computeroutput">steady_clock</code>.) Support may be disabled
          by defining <code class="computeroutput">ASIO_DISABLE_STD_CHRONO</code>, or explicitly enabled
          for other compilers by defining <code class="computeroutput">ASIO_HAS_STD_CHRONO</code>.
        </p>
<p>
          When standard <code class="computeroutput">chrono</code> is unavailable, Asio will otherwise use
          the Boost.Chrono library. The <a class="link" href="../../reference/basic_waitable_timer.html" title="basic_waitable_timer">basic_waitable_timer</a>
          class template may be used with either.
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<td align="right"><div class="copyright-footer">Copyright &#169; 2003-2018 Christopher M. Kohlhoff<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
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